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Understanding K ^trans: a simulation study based on a multiple-pathway model.

T S Koh^1,2, T P Hennedige¹, C H Thng^1,2

¹Department of Oncologic Imaging, National Cancer Center, 169610, Singapore.

Physics in Medicine and Biology

|May 4, 2017

Summary

This summary is machine-generated.

The transfer constant K^trans in MRI tumor imaging has unclear interpretation. Computer simulations reveal K^trans relates to plasma flow and extraction in slow and rapid vascular transit states, respectively.

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Area of Science:

Biomedical Imaging
Medical Physics
Radiology

Background:

Dynamic contrast-enhanced MRI (DCE-MRI) uses the transfer constant (K^trans) to assess tumor vasculature.
The precise interpretation and utility of K^trans as a biomarker remain uncertain.
A comprehensive tracer kinetic model with multiple pathways is needed for clarification.

Purpose of the Study:

To clarify the interpretation and application of K^trans in DCE-MRI.
To investigate the relationship between K^trans and physiological parameters under diverse transport conditions.
To utilize computer simulations for a deeper understanding of K^trans behavior.

Main Methods:

Simulated tissue concentration-time curves using a multiple-pathway (MP) model.
Fitted simulated data with generalized kinetic (GK) and extended GK models.
Assessed relationships between K^trans, plasma flow (F_p), vessel permeability (PS), and extraction fraction (EF_p) via correlation and regression analysis.

Main Results:

The MP model offers a two-tier interpretation of K^trans based on vascular transit time.
K^trans correlates primarily with F_p in slow transit states and EF_p in rapid transit states.
Vessel permeability (PS) and plasma flow (F_p) act as secondary constraints, influencing K^trans association with EF_p and PS in slow and rapid states, respectively.

Conclusions:

K^trans interpretation in DCE-MRI is dependent on vascular transit time.
The study provides a refined understanding of K^trans as a biomarker for tumor vasculature.
Computer simulations enhance the utility of K^trans analysis in clinical settings.